Portable electronic devices, such as cellular telephones, two-way radios, pagers, gaming devices, and remote control devices, commonly use rechargeable batteries to provide electrical power to the devices' components. Wireless charging of a device's rechargeable batteries can be accomplished by inductive means with a primary coil located in a charger base unit and a secondary coil located in the device. When power is applied to the charger base unit, a current is passed through the primary coil creating a magnetic flux. When the secondary coil of the portable electronic device is placed in close proximity to the primary coil, the magnetic flux couples to the secondary coil inducing a current in the secondary coil. The secondary coil is coupled to the device's battery compartment terminals. The current induced in the secondary coil is used to charge batteries installed in the battery compartment of the portable electronic device.
A problem facing wireless charging is that portable electronic devices come in a myriad of shapes and sizes. A further problem for inductive wireless charging is a lack of standardization in the industry with regard to the position of a secondary coil within the portable electronic device. In order for sufficient electrical energy to be produced by a device's secondary coil, the primary coil of the associated charger base unit and the secondary coil of the device must be positioned in close-enough magnetic proximity. Optimal charging or recharging of an electronic device cannot be achieved if the primary and secondary coils are not suitably aligned. Accordingly, a charger base unit for a particular device must have its primary coil positioned in a location that corresponds with the position of the device's secondary coil.
The lack of standardization in the relative positioning of the secondary coils, among other things, has resulted in unique or dedicated charger base unit for each portable electronic device or device type. Current charger base units typically are not adapted to provide wireless charging for devices having various geometries or with secondary coils placed in disparate locations within a similar geometry. Accordingly, a consumer with a plurality of wirelessly-rechargeable, portable electronic devices typically must also have a corresponding number of charger base units (e.g., one charger base unit for each portable electronic device). The cost, physical space, and power connectivity requirements for such a plurality of charger base units is significant.
Accordingly, it is desirable to provide wireless charging technologies that enable a single charger base unit to be capable of wirelessly charging the batteries of portable electronic devices having a variety of geometries (e.g., universal charging), without requiring a plurality of dedicated charger base units and power connectors. Furthermore, other desirable features and characteristics of the inventive subject matter will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.